Fairchild AUM-N-2/AQM-41Petrel

The Petrel was an early standoff anti-shipping missile, which was used by the U.S. Navy with moderate success for a brief
period in the 1950s, before it was converted to a target drone.

The history of Petrel dates back to August 1944, when the U.S. Navy BuOrd (Bureau of Ordnance) initiated the Kingfisher
project to develop a family of standoff torpedo weapons. This included the Kingfisher C, designated as SWOD
(Special Weapons Ordnance Device) MK 15, which was to be an air-lauched jet-powered torpedo-carrying missile. In late 1947,
Kingfisher C was designated as AUM-2 (changed to AUM-N-2 in early 1948) and renamed Petrel. After a long
development period, in which several completely different configurations were studied, tests of the XAUM-N-2 by the Naval Bureau
of Standards began in 1951. In 1954, development was transferred to Fairchild, and in April 1956 the AUM-N-2 finally became
operational.

Petrel was essentially a MK 21 homing torpedo, fitted with a nose cone containing the guidance equipment, a Fairchild J44
turbojet, and wooden wings and fins. Despite its AUM (Air-to-Underwater Missile) designation, it was suitable for use against surface
ships (and surfaced submarines) only. It was carried by Lockheed P2V-6B Neptune aircraft (later redesignated as P2V-6M, and
then MP-2F). After launch, it dove to an altitude of about 60 m (200 ft), and continued to the target at a speed of Mach 0.5, using
semi-active radar guidance. When it had closed to a distance of about 1400 m (4500 ft), the engine was stopped, all flying surfaces
and the engine were discarded, and the torpedo dropped into the water, where it homed on the target.

In the late 1950s, enemy surface ships were considered a relatively minor threat by the U.S. Navy when compared to the Soviet
submarine force. Therefore, the Petrel wasn't a high-priority weapon, and it was initially assigned to reserve units.
The AUM-N-2 had also severe operational shortcomings. Its rather low speed and semi-active guidance required the launching aircraft to come
relatively close to the target, which would have made the use of Petrel against ships with sophisticated air defenses problematic.
In January 1959, the AUM-N-2 was withdrawn from the operational inventory. Existing Petrel airframes were then used as
air-launched target drones, but were not redesignated in the KD (Target Drone) series.

Drawing: Kevin Wornkey

AQM-41A (without wings)

In June 1963, the remaining Petrel targets were redesignated as AQM-41A, but the last of the Petrels was probably
gone soon after.

Specifications

Note: Data given by several sources show slight variations. Figures given below may therefore be inaccurate!